Combination vaccines offer patients the advantage of receiving a reduced number of injections, which leads to the clinical advantage of increased compliance (e.g. see chapter 29 of reference 1).
Six pathogens of particular concern, particularly in children, are Corynebacterium diphtheriae (the cause of diphtheria), Clostridium tetani (the cause of tetanus/lockjaw), Bordetella pertussis (whooping cough), hepatitis B virus (‘HepB’, viral hepatitis), Haemophilus influenzae type b (‘Hib’, a cause of bacterial meningitis and pneumonia) and Neisseria meningitidis (meningococcal meningitis and septicaemia).
Vaccines against each of these pathogens are known, and a pentavalent vaccine including all five of the ‘D’, ‘T’, ‘P’, ‘HepB’, and ‘Hib’ components for simultaneous combined administration is marketed by GlaxoSmithKline under the name TRITANRIX-HepB/Hib. The ‘P’ component in this pentavalent vaccine is based on whole cell pertussis (‘Pw’) antigen. The DTP and HepB components of this vaccine are in a combined solution within a vial (and this tetravalent DTPw-HepB combination is sold separately as the ‘TRITANRIX-HepB’ product), but the Hib component is freeze-dried and contained in a separate vial. The DTPw-HepB solution is used to reconstitute the Hib component at the time of use, extemporaneously forming the pentavalent vaccine in the vial.
TRITANRIX-HepB/Hib does not protect against meningococcal infection.
Example 3 of reference 2 discloses the results of human clinical trials in which the tetravalent TRITANRIX-HepB product was extemporaneously mixed with conjugated capsular saccharides from Hib and from serogroups A and C of meningococcus (‘MenA’ and ‘MenC’). The authors report that this heptavalent mixture induced a good immune response against each antigen and was well tolerated by infants. Full details of the Hib, MenA and MenC components are not given. Similar information is reported in references 3 and 4.
It is an object of the invention to provide further and improved combination vaccines for protecting against all six of Corynebacterium diphtheriae, Clostridium tetani, Bordetella pertussis, hepatitis B virus, Haemophilus influenzae type b and Neisseria meningitidis. 